1. Field of the Inventive Concepts
The inventive concepts disclosed herein generally relate to medical implants, and more particularly but not by way of limitation to a meniscus implant for replacing damaged meniscal tissue and to a method for using thereof.
2. Brief Description of Related Art
The menisci are responsible for shock absorption, load transmission, lubrication, and stability of the knee joint. The menisci are important in reducing the incidence of degenerative joint disease. Unfortunately, after trauma or a severe injury the meniscus may be damaged, such as by fissures forming in the meniscus, for example. Damage to the meniscus is associated with changes in joint function that can lead to disability and degenerative joint changes. One of the strategies for meniscal repair suggests the use of biocompatible synthetic or natural scaffolds as a substrate to promote remodeling and healing of the defect. In case of too many fissures, the meniscus may have to be trimmed in a way that only an outer rim of meniscus may be left. A meniscus implant made of a synthetic or natural material may be anchored to the rim via surgical sutures, for example.
The discussion about meniscal repair has been characterized by the debate of meniscectomy (i.e., partial or complete removal of the native meniscus) versus meniscal repair. It has been shown that meniscectomy increases the risk of developing osteoarthritis of the knee joint. Whenever possible, native meniscus tissue should be preserved by surgically sewing and reshaping it to avoid loss of joint stability and the concentration of mechanical forces on the articular cartilage of the femoral condyle and the tibia plateau. In cases where a meniscectomy is inevitable, two different types of meniscus implants are available on the market. One is a fully-synthetic solution and the other is a natural solution based for example on purified Type-I collagen fibers. The synthetic and the natural solutions are scaffolds with a porous structure to promote tissue ingrowth. Both concepts are based on the anchorage to the rim and to the posterior and anterior horn of the meniscus with sutures or a dowel-like device.
An example on the market in the category of natural solutions is Menaflex™, formerly CMI, from ReGen Biologics (ReGen Biologics Inc., 411 Hackensack Avenue, Hackensack, N.J. 07601, USA). The Menaflex™ collagen meniscus implant is a resorbable collagen-based surgical mesh composed primarily of Type-I collagen. It serves to reinforce damaged or weakened meniscus tissue and provides a resorbable scaffold for replacement by the patient's own tissue. Menaflex™ is intended for use in patients with an irreparable meniscus tear, or loss of meniscus tissue. An example in the category of synthetic implant is Actifit™ from Orteq Bioengineering (Orteq Ltd, 10 Greycoat Place, London, SW1P 1SB, United Kingdom). Actifit™ is a resilient, flexible, highly porous, and biocompatible synthetic scaffold. Its structure comprises open continuous pores, through which blood vessels can rapidly grow into the implant. The blood transports cells and nutrients that initiate the growth of new meniscus-like tissue inside the synthetic scaffold.